JP5551922B2 - Electromagnetic actuator - Google Patents

Description

  The present invention relates generally to solenoid valve actuators for controlling valve actuation. More specifically, the present invention relates to an electromagnetic actuator adapted to control valve opening / closing timing in a compressor.

  Compressors are commonly used to increase the pressure of a working fluid by receiving power from an electric machine or turbine and applying a compressive force to the working fluid. The working fluid can be air, refrigerant or the like. Compressors are generally classified as positive displacement compressors, dynamic compressors or turbo compressors, depending on the method they employ for pressurization.

  Positive displacement compressors are generally used to increase the pressure of the working fluid by reducing the volume and can be further classified into reciprocating compressors and rotary compressors. A reciprocating compressor typically pressurizes working fluid by a piston that reciprocates within a cylinder. A rotary compressor typically pressurizes working fluid with rollers that rotate within an eccentric cylinder.

  Large industrial reciprocating compressors are often operated at a constant speed. Such a compressor can be operated at a partial load by controlling the opening and closing of the compressor intake valve. By changing the opening and closing timing of the compressor valve, the mass flow rate of fluid through the compressor is reduced. Thus, the overall performance of the compressor over a wide range of speeds and load ranges can be improved. One skilled in the art will appreciate that the phase angle between the crankshaft and the camshaft can be changed to adjust the valve timing event. In this way, it is possible to obtain improved performance over a wider range of engine operating characteristics and conditions than when the fixed valve opening / closing timing is employed.

  In one embodiment, the valve is actuated by an electromagnetic actuator having a solenoid. The solenoid includes at least one coil disposed within the core, the coil being coupled to a set of power electronics configured to supply current to the coil. The actuator further includes a plunger coupled to the anchor plate and at least one spring configured to guide the plunger. The opening and closing of the valve is controlled by passing a current through the coil. Conventional electromagnetic actuators have a relatively large mounting location. Since the coil is installed in the actuator housing, heat transfer from the coil to the ambient atmosphere is less efficient. As a result, the maximum allowable coil temperature limits the maximum force and operating speed of the actuator. Furthermore, high impact forces acting on the solenoids can affect the accuracy of the device, and as a result, can cause retention forces and operating speed drift over time. In order to reduce wear and keep the accuracy of the device at an acceptable level, it is necessary to select high performance materials and larger component dimensions.

US Pat. No. 5,352,101 A US Pat. No. 7,021,603 B2 US Pat. No. 7,063,077 B2 US Pat. No. 7,066,141 B2 US Pat. No. 7,225,770 B2

  An improved and smaller actuation system that is designed to control valve opening and closing timing in machines such as piston compressors to achieve flexibility during transient operation is desirable.

  In accordance with one exemplary embodiment of the present invention, a valve configured for use in a machine is disclosed. The valve includes a valve plate coupled to a movable device partially disposed within the housing. The electromagnetic actuator includes a first set of permanent magnets provided on the movable device. At least one stator core is disposed proximate to the movable device with a gap between the stator core and the movable device. At least one stator coil is wound around each stator core. A power source is coupled to the at least one stator coil and configured to supply current to the at least one stator coil. The opening and closing of the valve plate is controlled by changing the direction of current flow through the at least one stator coil.

  According to another exemplary embodiment of the present invention, a control unit is coupled to the power source and configured to control the supply of current to the at least one stator coil based on the load condition of the machine. The opening and closing of the valve plate is controlled by changing the direction of current flow through the at least one stator coil.

  According to another exemplary embodiment of the present invention, at least one stator core is disposed proximate to the movable device with a gap between the stator core and the movable device. A housing is disposed in the gap between the stator core and the movable device.

  These and other features, aspects and advantages of the present invention will be better understood when the following detailed description is read with reference to the accompanying drawings in which like reference numerals represent like parts throughout the drawings. Will come.

1 is a schematic view of a piston machine, such as a piston compressor having a solenoid valve actuation system according to an exemplary embodiment of the present invention. 1 is a schematic view of an intake valve assembly of a piston machine having a solenoid valve actuation system according to an exemplary embodiment of the present invention. 1 is a schematic view of a piston machine intake valve assembly having a solenoid valve actuation system with a stator core and a coil disposed externally of a housing, in accordance with an exemplary embodiment of the present invention. 1 is a schematic view of a suction valve assembly of a piston machine having a solenoid valve actuation system with a stator core and coils disposed within a housing, according to an exemplary embodiment of the present invention. 1 is a schematic view of a piston machine intake valve assembly having an electromagnetic valve actuation system with a plurality of permanent magnets having the same orientation provided on an anchor plate, in accordance with an exemplary embodiment of the present invention. FIG.

  As described in detail below, some embodiments of the present invention provide valves that operate in harsh environments within a machine, such as a piston machine having a piston disposed within a housing. It should be noted herein that in some embodiments, the valve is also applicable for use in high pressure and reduced pressure applications. In some other embodiments, the valve is also applicable to applications that require preventing fluid leakage and impurity ingress. As used herein, an expression without a number includes a plurality of objects unless the context clearly indicates otherwise. At least one valve is coupled to the housing. The valve includes a movable device partially disposed within the housing. The movable device is coupled to the valve plate. A linear electromagnetic actuator is configured to actuate the valve plate. The actuator includes a set of permanent magnets provided in the movable device, and at least one stator core arranged in proximity to the movable device with a gap between the movable device. In some embodiments, the control unit is configured to control the supply of current to the stator coil based on machine load conditions. In some embodiments, the piston machine is a piston compressor. It should be noted herein that the exemplary electromagnetic actuator functions like a “step motor”. The actuator provides a constant actuation force over the entire stroke of the piston. Therefore, better valve motion controllability is achieved. Also, the mounting location of the electromagnetic actuator is significantly smaller than the conventional design.

  Referring generally to FIG. 1, a piston machine 10 according to some aspects of this embodiment is shown. In the illustrated embodiment, the piston machine is a compressor 10 having a piston 12 slidably inserted into a cylinder 14. A suction valve assembly 16 adapted to open and close a suction hole 18 provided in front of the piston 12 is provided. The intake valve assembly 16 controls the intake of fluid through the intake hole 18. The compressor 10 further includes a linear electromagnetic actuator 20 adapted to pressurize the fluid by controlling the opening and closing of the intake valve assembly 16 during the compression stroke of the compressor 10. The control unit 22 can be configured to couple to the electromagnetic actuator 20 and to control the operation of the electromagnetic actuator 20. Details of the electromagnetic actuator 20 will be illustrated and described in more detail with reference to embodiments described later.

  It should be noted herein that the illustrated configuration of the piston compressor is an exemplary embodiment and should be construed as non-limiting. In other embodiments, the piston compressor can further include optional and exemplary aspects. The reciprocating compressor 10 can be used for household and industrial purposes. The compressor 10 is typically driven by an electric motor, a steam or gas turbine, a combustion engine, or the like. As will be appreciated by those skilled in the art, the compressor 10 can be used to pressurize air, hydrogen, methane, butane, or other liquids or gases. It should also be noted that the electromagnetic actuator 20 described herein is also applicable to other applications, including harsh environments in other machines.

  Referring to FIG. 2, a linear electromagnetic actuator 20 adapted to control the opening and closing of the intake valve assembly 16 is shown. The intake valve assembly 16 includes a movable device 24 partially disposed within a housing 26. In the illustrated embodiment, the movable device 24 includes an anchor plate 28 partially disposed within the housing 26, with a portion 30 of the anchor plate 28 protruding from the housing 26. A portion 30 of the anchor plate 28 is coupled to an unloader rod (push rod) 32. The push rod 32 is coupled to a valve plate 34 that is movably disposed on a valve seat 36. In other embodiments, the configuration of the valve plate 34 and the valve seat 36 can vary depending on the application.

  In one embodiment, the housing 26 is a high pressure housing that allows for higher actuation forces. In another embodiment, the housing 26 can have thinner walls and can include a high pressure seal 37 to maintain a predetermined pressure within the housing.

  In the illustrated embodiment, the actuator 20 includes a first set of permanent magnets 38 having alternating orientation / polarity disposed about the anchor plate 28 within the housing 26. The number and configuration of the first permanent magnets 38 can be changed depending on the application. A plurality of stator cores 40 are disposed in proximity to the anchor plate 28 with a gap 42 provided between the stator core 40 and the anchor plate 28. It is noted herein that in this illustrated embodiment, the housing 26 is disposed within the gap 42 between the stator core 40 and the anchor plate 28. A plurality of stator coils 44 are wound around each stator core 40. Note that the number and configuration of stator cores 40 and stator coils 44 can vary depending on the application. A power source 46 is coupled to the stator coil 44 provided in each stator core 40 and is configured to supply current to the stator coil 44.

  The control unit 22 is coupled to the power source 46 and is configured to control the supply of current to the stator coil 44 based on the load condition of the machine 10. The opening and closing of the valve plate 34 is controlled by changing the direction of current flow through the stator coil 44. In one embodiment, the control unit 22 includes a user programmable electronic logic controller. The control unit 22 can control the valve actuator based on the load state of the compressor 10. Those skilled in the art will appreciate in light of this description that several compressor configurations are possible.

  In some embodiments, the control unit 22 can further include a database, an algorithm, and a data analysis block (not shown). The database can be configured to store predetermined information regarding the compressor 10. For example, the database may store information regarding crank angle, compressor speed, compressor load, suction fluid pressure, pressurized fluid pressure, fluid type, or the like. The database can also include an instruction set, map, lookup table, variable, or the like. Such maps, look-up tables and instruction sets allow the characteristics of the valve assembly to be specified compressor operating parameters such as compressor speed, crank angle, compressor pressure, compressor load, fluid type or the like. Work to correlate. Further, the database can be configured to store information regarding the compressor 10 that is actually detected / detected. The algorithm may allow processing of detection information regarding the compressor 10.

  The data analysis block may include various circuit types such as a microprocessor, programmable logic controller, logic module, or the like. Using a data analysis block in combination with an algorithm, various related to the determination of the closing timing of the intake valve, the predetermined time period to control the opening and closing of the valve, the power required to drive the valve, or the like Can be performed. Any of the above parameters can be adapted or changed selectively and / or dynamically over time.

  The valve plate 34 is configured to move between a “closed position” and an “open position” to block or allow fluid flow, respectively. In the illustrated embodiment, the valve plate 34 is in the closed position, ie, the valve plate 34 is in contact with the valve seat 36. When the valve plate 34 is in the open position, the valve plate is not in contact with the valve seat 36. The valve plate 34 is opened by actuating the movable device 24 downward so that the valve plate 34 moves away from the valve seat 36. The movement of the movable device 24 is controlled by controlling the supply of current through the stator coil 44. When the supply of current to the stator coil 44 is interrupted, the valve plate 34 moves to the closed position. When current is supplied to the stator coil 44, the stator core 40 generates an electromagnetic force that cooperates with the first set of permanent magnets 38 to pull the anchor plate 28 downward. As a result, the unloader rod 32 coupled to the anchor plate 28 is also pushed downward so that the valve plate 34 moves away from the valve seat 36. As a result of this downward movement of movable device 24 (indicated by arrow 50), valve plate 34 is pushed away from valve seat 36 and valve plate 34 opens. As long as current is supplied to the stator coil 44, the electromagnetic force generated by the actuator 20 biases the movable device 24 so that the valve plate 34 moves away from the valve seat 36, and thus by the reverse fluid flow through the valve. The valve plate 34 is kept open against the generated force.

  In some embodiments, the amount of opening and closing of the valve plate 34 is controlled by controlling the direction of current supply (current flow) through the stator coil 44. In one embodiment, the actuator 20 is used to maintain the valve plate 34 in an open position for a predetermined time. The longer the valve plate 34 is kept in the open position during the compression stroke, the more gas will be pushed back into the suction pipe and the less gas will be delivered to the discharge pipe of the compressor. . The amount of gas delivered by the compressor 10 can be controlled by controlling the opening time of the valve plate 34.

  In the illustrated embodiment, a biasing device 39 is disposed between the movable device 24 and the housing 26. The biasing device 39 operates the actuator 20 and biases the valve plate 34 to a predetermined position (which can be an open position or a closed position) when the power supply to the electromagnetic actuator 20 is interrupted or interrupted. Configured as follows. In one embodiment, this ensures that the valve plate 34 is not in the open position when the power supply to the electromagnetic actuator 20 is interrupted. In the illustrated embodiment, the biasing device 39 includes a biasing spring. In other embodiments, other suitable biasing devices are also contemplated.

  In some embodiments, the solenoid valve actuator 20 is employed to control the closing of the intake valve assembly 16 during the compression stroke of the compressor 10 in unloaded or part load operating conditions. In this illustrated embodiment, a single intake valve assembly 16 is shown, but the compressor 10 can include a plurality of intake valves adapted to control the intake of fluid into the compressor. One electromagnetic actuator can be provided for each valve to operate each valve separately and to ensure flexibility. For example, depending on the compressor load conditions, it may be necessary to change the closing time of one valve set from the closing time of another valve set during the compressor compression stroke. . It should be noted herein that this exemplary valve actuation system is applicable to other valves that operate within the harsh environment of the machine.

  As previously described, the actuator 20 provides a constant actuation force over the entire stroke of the piston, thereby improving motion controllability. The housing 26 of the actuator 20 is arranged between the stator core 40 and the anchor plate 28, which facilitates the enforcement of the safety regulations, so that there are no electrical components arranged inside the compressor. . Further, since the stator coil 44 is disposed outside the housing 26, the cooling thereof is easier. The mounting location for this actuator design is significantly smaller. Therefore, there is no adverse effect on the overall performance of the actuator 20. Further, since the stator core 40 does not come into contact with the movable device 24, the impact force between the movable device 24 and the stator core 40 is limited.

  Referring to FIG. 3, a linear electromagnetic actuator 20 adapted to control the opening and closing of the intake valve assembly 16 is shown. In the illustrated embodiment, the configuration of the actuator 20 is similar to the embodiment shown in FIG. 2 except that the biasing device 52 is disposed inside and outside the housing 26. The biasing device 52 includes a set of second permanent magnets 54 disposed outside the housing 26 and a set of third permanent magnets 56 disposed around the anchor plate 28 within the housing 26. Similar to the previously described embodiment, the biasing device 52 is configured to actuate the actuator 20 and bias the valve plate 34 into place when power supply to the electromagnetic actuator 20 is interrupted or interrupted. . In other embodiments, other suitable biasing devices are also contemplated.

  The actuator 20 can be actively moved upward or downward depending on the direction of current flow through the stator coil 44. The actuation force is constant throughout the piston stroke. The coil 44 can be molded using a molding material configured to improve heat transfer from the coil 44 to the ambient atmosphere. The coil 44 is not in contact with gas, thereby preventing sparks in the actuator.

  Referring to FIG. 4, a linear electromagnetic actuator 20 adapted to control the opening and closing of the intake valve assembly 16 is shown. In this specification, in the illustrated embodiment, the configuration of the actuator 20 is the same as that of the embodiment shown in FIG. 3 except that the stator core 40 and the stator coil 44 are disposed in the housing 26. Please pay attention. The stator coil 44 and the stator core 40 are disposed inside the housing 26, thereby reducing the gap 42 between the stator core 40 and the anchor plate 28. This allows the actuator 20 to provide a higher actuation force. There is no direct impact between the stator core 40 and the anchor plate 28, resulting in reduced wear and adverse effects on device accuracy.

  Referring to FIG. 5, a linear electromagnetic actuator 20 adapted to control the opening and closing of the intake valve assembly 16 is shown. Herein, in this illustrated embodiment, the configuration of the actuator 20 has the same alternating orientation / polarity as the first set of permanent magnets 38 is disposed around the anchor plate 28 within the housing 26. Note that this is the same as the embodiment shown in FIG. A plurality of iron teeth 58 are arranged between permanent magnets 38 having the same alternating orientation / polarity. The actuator 20 of the embodiment described with reference to FIGS. 1-5 provides a much higher actuation force at the beginning of the piston stroke and provides a constant actuation force over the remainder of the piston stroke.

  Although only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. Accordingly, it is to be understood that the appended claims are intended to protect all such modifications and changes as fall within the scope of the spirit of the invention.

10 piston machine 12 piston 14 cylinder 16 suction valve assembly 18 suction hole 20 linear electromagnetic actuator 22 control unit 24 movable device 26 housing 28 anchor plate 30 part 32 unloader rod 34 valve plate 36 valve seat 37 high pressure seal 38 first permanent magnet 39 Energizing device 40 Stator core 42 Gap 44 Stator coil 46 Power supply 50 Downward movement 52 Energizing device 54 Second permanent magnet set 56 Third permanent magnet set 58 Iron teeth

Claims (9)

A valve configured for use in a machine,
A movable device (24) partially disposed in the housing (26);
A valve plate (34) coupled to the movable device (24);
A linear electromagnetic actuator (20);
The linear electromagnetic actuator (20) includes:
A set of first permanent magnets (38) provided in the movable device (24);
At least one stator core (40) disposed proximate to the movable device (24) with a gap (42) between the movable device (24) and
At least one stator coil (44) wound around each stator core (40);
A power source (46) coupled to the at least one stator coil (44) and configured to supply current to the at least one stator coil (44);
Opening and closing of the valve plate (34) is controlled by changing the direction of current flow through the at least one stator coil (44) ;
The housing (26) is disposed between the at least one stator core (40) and the movable device (24).
A valve characterized by that . The valve of any preceding claim, wherein the valve includes a suction valve (16) configured for use with a piston compressor (10). The valve of claim 1 or 2 , further comprising a high pressure seal (37) configured to maintain a predetermined pressure within the housing (26). The first further comprising teeth (58) made more iron disposed between pairs of permanent magnets (38), any one valve according to claims 1 to 3 having the same polarity. A biasing device (39, 52) disposed between the movable device (24) and the housing (26);
The biasing device (39, 52) is configured to bias the valve plate (34) to a predetermined position when power supply to the at least one stator coil (44) is interrupted or interrupted. ,
The valve according to any one of claims 1 to 4 . Further comprising a biasing device (39, 52) disposed outside the housing (26);
The biasing device (39, 52) is configured to bias the valve plate (34) to a predetermined position when power supply to the at least one stator coil (44) is interrupted or interrupted. ,
The valve according to any one of claims 1 to 4 . A valve configured for use in a machine,
A movable device (24) partially disposed in the housing (26);
A valve plate (34) coupled to the movable device (24);
A linear electromagnetic actuator (20);
The linear electromagnetic actuator (20) includes:
A plurality of permanent magnets provided in the movable device (24);
At least one stator core (40) disposed proximate to the movable device (24) with a gap (42) between the movable device (24) and
At least one stator coil (44) wound around each stator core (40);
A power supply (46) coupled to the at least one stator coil (44) and configured to supply current to the at least one stator coil (44);
A control unit (22) coupled to the power source (46) and configured to control the supply of current to the at least one stator coil (44) based on a load condition of the machine;
Opening and closing of the valve plate (34) is controlled by changing the direction of current flow through the at least one stator coil (44) ;
The housing (26) is disposed between the at least one stator core (40) and the movable device (24).
A valve characterized by that . The valve of claim 7 , wherein the movable device (24) includes an anchor plate (28) partially disposed within the housing (26). A valve configured for use in a machine,
A movable device (24) partially disposed in the housing (26);
A valve plate (34) coupled to the movable device (24);
A linear electromagnetic actuator (20);
The linear electromagnetic actuator (20) includes:
A plurality of permanent magnets provided in the movable device (24);
The gap at least one stator core disposed proximate to (42) One or provided with the movable unit (24) (40) between said movable device (24),
At least one stator coil (44) wound around each stator core (40);
A power source (46) coupled to the at least one stator coil (44) and configured to supply current to the at least one stator coil (44);
Opening and closing of the valve plate (34) is controlled by changing the direction of current flow through the at least one stator coil (44) ;
The housing (26) is disposed between the at least one stator core (40) and the movable device (24).
A valve characterized by that .

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